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Fluorescence Lifetime Imaging of Molecular Rotors in Living Cells
Published on: February 9, 2012
Intracellular temperature mapping with a fluorescent polymeric thermometer and fluorescence lifetime imaging
Kohki Okabe1, Noriko Inada, Chie Gota
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan.
Nature Communications
|March 20, 2012
Summary
Researchers developed the first intracellular temperature mapping technique using a fluorescent polymeric thermometer. This method reveals temperature differences within cells, linking temperature to organelle function.
Area of Science:
- Cellular Biology
- Biophysics
- Microscopy
Background:
- Intracellular temperature is a critical regulator of cellular functions and biochemical reactions.
- Accurate intracellular temperature mapping is essential for biological and medical advancements but has been technically challenging.
- Previous methods lacked the resolution or capability for precise intracellular thermometry.
Purpose of the Study:
- To develop and demonstrate the first method for intracellular temperature mapping.
- To investigate the spatial distribution of temperature within living cells.
- To explore the relationship between intracellular temperature and organelle function.
Main Methods:
- Development of a novel fluorescent polymeric thermometer.
- Utilization of fluorescence lifetime imaging microscopy (FLIM) for temperature sensing.
- Application of the technique to COS7 cells for intracellular thermometry.
Main Results:
- Achieved spatial resolution at the diffraction limit (200 nm) and temperature resolution of 0.18–0.58 °C.
- Observed significantly higher temperatures in the nucleus and centrosome compared to the cytoplasm.
- Detected cell cycle-dependent temperature variations between the nucleus and cytoplasm.
- Visualized localized heat production from mitochondria.
Conclusions:
- The developed fluorescent polymeric thermometer and FLIM enable unprecedented intracellular temperature mapping.
- Intracellular temperature distribution is non-uniform and varies across organelles and cell cycle stages.
- This thermometry technique provides a new tool to understand the intrinsic link between temperature and organelle function.
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